Sorry, but I'm not going to be nearly as kind as others have been. I would have kept silent till I read that you planned to take the most precious cargo in the world for rides with it: your kids!

What I see in those photos is a recipe for disaster, add in pain and death if it ever saw a human passenger. Pics aren't clear enough to tell for sure but that looks like hardware store all-thread as your main support structures? Do you have any idea of the actual metallurgy and strength of that stuff you used, that's possibly made in China depending where purchased? That is its strength in relationship to Grade 3, Grade 5, Grade 8 or ungraded?

With the all-thread bolts hanging out in space what's supposed to support sidecar dynamic loads, cornering forces, flexion? The metal tab used on that front support clamp doesn't look nearly thick enough to function as a clamp, even enough to withstand necessary forces to tighten it in place, let alone support a load.

The tubing dimensions look too small and too thin walled for any genuine structural integrity or load-bearing strength. There's a direct relationship between tube dimensions/wall thickness and structural load carrying ability. I'd say you need to do more research there. Also gussets are needed at all angled joints, especially the rear.

As that's currently built I would hesitate to use it to hang a heavy saddle bag. I'd have kept my mouth shut if it wasn't for the possibility of that setup causing extremes of pain, injury and even death for whatever innocents get involved. Please do more research and accept the other member's prior suggestions and offers of guidance. I just don't want to see you or anybody else get hurt or killed, especially your children!

Sorry, but I'm not going to be nearly as kind as others have been. I would have kept silent till I read that you planned to take the most precious cargo in the world for rides with it: your kids!

What I see in those photos is a recipe for disaster, add in pain and death if it ever saw a human passenger. Pics aren't clear enough to tell for sure but that looks like hardware store all-thread as your main support structures? Do you have any idea of the actual metallurgy and strength of that stuff you used, that's possibly made in China depending where purchased? That is its strength in relationship to Grade 3, Grade 5, Grade 8 or ungraded?

With the all-thread bolts hanging out in space what's supposed to support sidecar dynamic loads, cornering forces, flexion? The metal tab used on that front support clamp doesn't look nearly thick enough to function as a clamp, even enough to withstand necessary forces to tighten it in place, let alone support a load.

The tubing dimensions look too small and too thin walled for any genuine structural integrity or load-bearing strength. There's a direct relationship between tube dimensions/wall thickness and structural load carrying ability. I'd say you need to do more research there. Also gussets are needed at all angled joints, especially the rear.

As that's currently built I would hesitate to use it to hang a heavy saddle bag. I'd have kept my mouth shut if it wasn't for the possibility of that setup causing extremes of pain, injury and even death for whatever innocents get involved. Please do more research and accept the other member's prior suggestions and offers of guidance. I just don't want to see you or anybody else get hurt or killed, especially your children!

Speaking of flex....some may say that sidecars do not create much stress etc on mounts in 'normal' use. This is really not true. Although one may not see a failure right away that does not mean it will not occur. Almost anything that flexes is prone to failure at some point. Bend a paper clip back and forth a few times and it will break. OVERBUILDING is far bette than underbuilding!! Good friend Hal Kendall used to say " build it stout out of things you know about" !! Not a bad thought.
Anything that is fabricated does have some chance of failure. All the cars do not finish the Indy 500 every year. In racing crashes are inevitibale but the ones that come from a failure of a part do get the attention of everyone right away. There ar epictures of some pretty good builds here at ADV. DON'T SKIMP!! The pictures just posted by D. Batchel are definately on the right track.
Again, I am not wanting to be critical but sometimes ya just gotta do what ya gotta do.

Believe me, Slade, I hate to be hyper-critical in public. However three things overshadow my holding back from comment. First, he said he plans to take his kids for rides in this rig! To me there's nothing more valuable in all the world than a man's children. I'd rather step on toes to protect them than be the cause of their inury or death by my silence.

Second, I have no idea of knowing how fast the build will progress, so for all I know he could be taking the kiddies for a ride this afternoon!

Third, if that is indeed hardware store all-thread, ungraded, possibly made in the orient of vastly inferior materials and production methods and heat treating, then no amount of waiting will make things get better. If that's what it is it's never going to be up to the task demanded of it and that's the main support of the whole sidecar rig!

I mulled it over for awhile, after also reviewing his posts on another sidecar forum, and could not remain silent. It's unfortunate and I really didn't want to comment at all, but saw and still see it as necessary, for the sake of his innocent little kids if nothing else!

I think these are all valid concerns that were voiced in a respectful and helpful manor. Being a novice hack builder myself....I hope I can swallow my pride and and listen to those that know more than I do. I look at everything as a learning experience. But I also hope and pray that my "learning" doesn't get anyone hurt. I'm sure this Bullet build will turn into an awesome little hack. I cant wait to see where he goes with the build progress.

I think these are all valid concerns that were voiced in a respectful and helpful manor. Being a novice hack builder myself....I hope I can swallow my pride and and listen to those that know more than I do. I look at everything as a learning experience. But I also hope and pray that my "learning" doesn't get anyone hurt. I'm sure this Bullet build will turn into an awesome little hack. I cant wait to see where he goes with the build progress.

Good post..... and, no matter what annyone thinks or says we are ALL learning

I just want to see good builds that are thought out.
It's all a compromise but it needs to have some basic engineering standards. Unless it's a leaner I'm looking for no flex at all. One unit.

Hell, I don't even like the idea of Heim or spherical joints used in place of an eye and clevis. Use an end that is intended to be rigid, not some linkage for a 3-point PTO.

Oh.... and Claude, just a correction on my name.
It gets botched up a bit, not Batch-tel but Bach-tel.

Don Bachtel in Nipomo.

Agree on the heims even though many well respoected builders use them.
To th eoriginal poster: Again please try and take what has been written here constructively. Most here are not prone to criticizing just to do so. I feel that everyone here at least up to this point has been trying to help you have a great build.

I may have an extra Velorex-style U-clamp kicking around somewhere that you could clamp to your downtube to replace that threaded rod. Probably not the /best/ way to do it, but I think it would hold a lot better than how it is now. Although I 'spect you could achieve the same thing with just an eye bolt and a couple lengthwise halves of pipe of an ID close to the OD of your downtube, underneath of the U bolts, to spread the force out more. They /will/ slip though, if you catch much air or big potholes, unless you torque them down to where they start crushing the downtube. I ended up welding mine to the frame to make it stop slipping.

I'm not trying to be critical either! :) Just would hate to see all that work end up breaking and/or injury! I think this is going to be a really cool build (I've always had a soft spot for REs)!!!

I likely don't know what I am talking about, but if I were me, I think I'd redesign a little bit, or add more material, trying to get triangles pointing in different directions going on. I think that would resist flex a lot better than the squareness you've got going on there. Something heading straight from the downtube to the lower subframe, without the horizontal piece of threaded rod.

I'd be a shade scared that the tubing you are using is a little too small, too. Maaaaybe if it was round, but I think you've gotta go extra beefy with the square stuff...

Here's what I did on my Greeves.. up front sandwiching the engine plates,

Your subframe doesn't have to be one piece, you just need four good points that will enhance and strengthen the bikes frame to create a unified structure.

I did something almost exactly like that on my CB400, too, except with no welding (and a lot uglier). Hang on a sec and I'll go out and take pictures.....

Jeez, that is one dirty mowdur-sickle!!! Ignore the oil that pukes out of the valve cover; it runs just fine! >_>

My top mount there is a Velorex U-clamp. It is "stock", except that the bolt holding the clevis and eye together was replaced with a hardened bolt. I also used a flat washer on each side everywhere, and a lock washer under every nut.

The bottom front mount is two pieces of angle cut out of a worn out grain blower chute and shaped to fit the motor mount. The four (can only see one peeking out in the picture) motor mount bolts have been replaced with longer hardened bolts (so as to reach through the extra thickness of the angle. The two angle pieces are stiffened up with a piece of 3/16 sheet steel across them, which is held on with hardened 1/4" bolts.

I don't like how the clevis on the lower front has to stick out so far. It's on my list of things to change this spring, if it doesn't break first.

Both of the rear mounts are attached using short pieces of 3/16" angle iron. The lower rear bolts onto the footpeg mount, and the upper rear bolts to the fender mount. They are the threaded block and eye bolt from a couple of other velorex U-clamps, sans U-pieces. The eye bolt tightens down against the inside of the angle iron. Both of them bolted through to the angle with two high-grade bolts. These were the ones I thought were most likely to shear off, but so far they have been just fine.

This has held for me for the most part, so far, with all three wheels off the ground a few times. But I don't have any kids riding around it in, just gear, nor do I have a family to support that would be inconvenienced if I hurt myself. ;) I lost the bolt that attaches the lower rear arm to the sidecar once. I don't know if I forgot to torque it down, or if it sheared off. After that happened, I torqued the crap out of all of those 6 with an air ratchet, and haven't had any more problems (with the sidecar, anyway; the rubber parts on that 35-year old engine are another story!).

Oh, and by the way: Take up Claude on his offer and give him a call. I did the same when I was putting mine together (though all bad design decisions of my build are mine, not his!). He's a very nice guy, and happily took time out of his day to give me a ton of excellent advice on setting up the outfit, without trying to sell me a thing. Thanks, Claude! If I ever have enough extra Real Money to get a Real Outfit built, I'll be calling you again. ;P

I think I'd have a go at using flat stock to sandwich the engine plates and up the downtube.
Couple of clever breaks for offsets and some custom blocks to surround the tube.
There's plenty of room up front for heavy wall tubing, welded and press fitted into 3/16" steel.
Pass a 16 mm stud thru the center and you'll be good to go. Grab the front two and you're half way there.
I'm still thinking about the rear. Start with cardboard and move on to masonite as templates.

Took me 9 months of figuring to do my first and only sidecar. The Greevorex.